Interlock for steel files



Dec. 1, 1942- w. F. REGENHARDT 2,304,020

INTERLOCK FOR STEEL FILES Filed Nov. 24, 1959. 3 Sheets-Sheet 1 INVENTOR W i/felg F. K27 M M T ATTORNEY y ,Dec. 1, 1942. w. F. REGENHARDT 2,304,020

INTERLOCK FOR STEEL FILES Filed Nov. 24, 1939 3 Sheets-Sheet 2 A..En

I 6 4 L INVENTOR P79 7 I W IyF Wy /75 M? A'ILTORNEY Dec. 1, 1942.

w. F. REGENHARDT- -INTERLOCK FOR STEELQFILE$ l a Sheets-Sheet 5 Filed Nov. 24, 1939 Patented Dec. 1, 1942 m'rmtoonrons'mnr. mes Walter Ftltegenhardt, Cleveland, Ohio Application November '24, 1939, Serial No. 305,793

laclaims. 01312.411)

5 key similar to the key used for locking adjacent walls together.

The present invention relates to improvements in filing cabinets and more particularly to filing cabinets of the type comprising a plurality of. individual cases which are interlocked-with'one another to form the cabinet. A cabinet similar to they present type is disclosed in my copending Still-another objectof vide a plate connectingtwo'walls of 'two adapplication S. .N. 240,177, filed NovemberlZ, 1938,

the present application being a continuation in part of the application mentioned above...

One of the objects of the present invention is to provide one of the cases with an opening in a wall thereof-which is adapted to receive a locking member of another, case,I the locking member being provided with a key receiving opening and a shoulder, and, to provide a key having a leg which is adapted to extend into the openin of the locking memberand also having. a shoulder which engages the shoulder of the locking member so that the leg of the key interlocks the cases and the abutting shoulders prevent the acciden- L" tal removal of the key.

Another object of the present invention is to provide at least part of the key of flexible and resilient material so that the shoulder portion may be flexed whereby it may slide over the lockder to shoulder engagement with the locking member when the'locking member. is inserted in,

position.

A further object of the present invention is to form the interlocking legof the key-of flexible jacent-cases, which walls are disposed in a common plane, the plate and walls having means for slidably attaching onejend of the plate'with each case,. the plate having locking members, similar to the lockingmembers on the walls of the cases; which locking ,members extend through a lock receiving opening in each of the two cases, and-locking the plate inposition by keys similar to the key used in looking the adjacent .walls together.

-When a filing cabinetis formed of two or more -.relatively tall stacks "of file cases, there is a I tendency for the stacks to bulge outwardly from one another. It is another object ofthe present 1 invention to attach the stacks with one another intermediate the tops and bottoms thereof by a plate'having a portion interposed between two cases of one stack and another-portion interposed between two cases of the next adjacent stack, the plate having openings in the men- 25 ing member and so that it will assume its shoultioned-portions thereofthrough which the protruding locking members of the cases extend, the edges of the openings cooperating with the locking 'members to prevent separation of the resilient material so that this leg frictionally binds the caseswith oneanother.

Usually .the drawers within the casings'are provided with gliders which space the bottoms of the -drawers from the floorsof the cases and it is a further object of the present invention to interpose the locking mechanism intermediatev these gliders and in the space between the floorof the case'and the bottom of the drawer.

-A still further object of the invention is to provide locking members on two walls of adjacent cases, which walls are disposed substantially in a common plane, so that'the key may be utilized in the manner set forth above to tiethe two walls togetherL- d A further object of the invention is to provide locking. members on two'walls of two adjacentcases, which .walls are disposed substantially in a common plane, and providing a' plate having means for interlatching one end thereof with each wall, the plate also having openings for receiving a locking nember of each of .the two adjacent cases of-the adjacent stacks.

Further-objects and advantages will be apparent from the following description, reference being had to the'accompanying drawings wherein a preferred :iorm of embodiment of the pres-'- ent invention is clearly disclosed.

In the drawings: Fig. -1' is a longitudinal sectional view taken on line :l- -l of Fig.2; v r

' Fig. 2 is a top view in section, the section being taken on line, 2 2 of Fig. l;

Fig.- 3 is a fragmentary sectional view 'of two file cases showingthe bottom and top walls respectively of one case about to be interlocked with another case;

cases for tying the forward ends of the cases to-' gether and locking the plate inposition with a I ing key;

Fig.4 is aperspective view of part of a filing cabinet, one of the drawers being removed; Fig; 5 is atop plan view of .a connecting plate; Fig. 6 is a sectional. view takenon line 6-6 of 5;' i

Fig. 7 is a sectionalviewof a second connecting plate;

Fig. 8 is a top' plan view of an improved lock- Fig. 9 is a sectional "view taken on line 9--9 Fig, 10is a perspective view, partly in section,

the invention is to pro- 2 oi the lower portion of the cabinet shown in partially completed Fig. 14 is a perspective view of an interlocking plate on an enlarged scale.

Referring to the drawings, there is shown in Fig. 4, a filing cabinet comprising a plurality of individual file cases 2|, interlocked together. Each of the cases includes asheet of metal fashioned to form a rectangular sleeve, including side walls and 26, a bottom wall 21 and a top wall 28. The ends of the sheet forming such walls may be secured together, preferably at the bottom by butt welding or may be overlapped and then welded as shown in Fig. 2. A reenforcing ring is disposed within the front end of the case and may be suitably secured to the sheet metal walls as by welding. The back of each case is closed by a sheet metal wall 3|. Each of the cases receives a drawer 33 through the open front thereof and the bottom wall 34 of the drawer is provided with spaced gliders 35. The construction thus far specifically described is similar to that shown in my Patent No. 2,123,803 issued July'l2, 1938.

The top walls of each of the cases are pierced and bent to form two spaced openings 31 and ledges 38, and the bottom walls of the cases are similarly pierced and bent to provide two spaced tongues 38 which are received in the openings 31 when one case is placed upon another having the sides thereof in alignment, and slid rearwardly as illustrated in Figs. 3 and 1 respec-' tlvely. The tongues 39 are thus interlatched with the top walls of a lower case. The cases are unlatched by sliding the upper casing forwardly to the position shown in Fig. 3. Preferably this interlatching mechanism is disposed or formed adjacent the rear of the cases.

The front ends of the cases are provided with an interlocking mechanism. This mechanism is formed by piercing the bottom walls of the cases to provide two spaced openings 4| (see Fig. 3) and shearing and bulging the top walls of the cases to form two spaced projecting or locking members 42. The locking members 42 of one case are arranged to extend through the openings 4| of another case when the tongues 38 are interlocked with the lower case as described above. Such positions of these parts are shown in the lower part of Fig. 1. The side walls of the openings 4| are arranged to closely embrace the side walls of the locking members 42 so as to maintain alignment between the cases. The drawn locking members 42 form recesses 43 on the undersides thereof. The front of the locking members are each provided with an opening 44 forming the mouth to the recess 43. The opposite sides of the members 42 provide shoulders 45 and the under sides of the members 42 provide abutments 4B. When the members 42 are in position in the openings 4|, part of the mouth of the recesses and part of the shoulders 45 project into the next above case. In the preferred embodiment the shoulders 45 are formed on the front of the members 42 while the mouths 44 to the recesses 43 are disposed at the rear 75 of the members 42. .It is to be understood that the openings 4| and the locking members 42 may be provided in any of the adjacent walls of the cases.

A key 41 is provided for interlocking two stacked cases. Preferably this key is formed of flexible and resilient sheet metal and isfurcated to form two key legs 48 and an intermediate leg or section 50. The key legs 48 are bent as shown at 5| and these legs are inserted into the upper part of the recesses 43 through the mouths 44 when the' members 42 are in position in the openings 4|, the bottom of'the key resting on the top side of the bottom wall 21 of a case while the top edges of the bulged portions 5| frictionally engage the undersides 46 of the locking members. In inserting the key legs 48 in position, the forward parts of the leg 58 rest upon the top of the locking members 42. Then the ends of the key legs 48 are forced downwardly and pulled forwardly, the material of the key 41 being sufllciently flexible to permit theflexing necessary. The fore part of the legs 50' are provided with outwardly projecting portions 52 which form rearwardly facing shoulders 53.

These shoulders are arranged-to slide over the forward part of locking members 42 and since the key 41 is formed of resilient materiaL'the shoulders 53 will abut the shoulders of the locking members 42 to prevent accidental .dis-

placement of the key 41.

It will be seen that the bulged portions 5| start rearwardly of the fore part of legs 48. The

flat fore part of either of legs 48 can be readily inserted into the mouth 44 of a member 42 although the mouth extends only a very short distance above the bottom wall 21. The front part of the bulged portion 5| slopes upwardly gradually and therefore functions as a cam and when the key is pulled into position, it forces the adjacent confronting walls of the cases into binding relation with one another. Thus it is apparent that the key can be readily attached although the confronting walls of adjacent cases 7 are warped or bent, for example, a bottom wall of an upper case may be bulged upwardly or the top wall of a lower case may be bulged downwardly and, in either event, the fore or flat parts of the legs 48 can be readily started into the mouths 44 and the confronting walls will be cammed toward and into binding relation with one another by the bulges 5| when the key is pulled to locking position.

The material from which key is formed is sufficiently flexible so that the leg can be lifted either by ones fingers or a small tool, and in order .to 'unlock the cases, it is necessary'only to lift upwardly on the forward end of the key leg 50 and push rearwardly on the key whereby the key legs 48 will be removed from the recesses 43. Then by lifting the unlocked case so that the openings 4| are' clear of the members" and then by pulling forwardly on the unlocked case to remove tongues 39 from engagement with the underside of the top wall 28, the case can be removed from the cabinet.

When the filing cabinet 20 is formed of two or more stacks of file cases 2| interlocked together as described, it is desirable to tie the stacks together to form a unitary structure. The

top cases of the stacks are tied together by aprovide two tongues 64 that are similar to the tongues 39. The top walls of adjacent cases on the top of the stacks lie substantially in a common plane, and these top walls are connected by the plate 60. The tongues 64 are inserted into the openings 31 adjacent the adjoining edges of the top cases by sliding the plate rearwardly. The openings 65 are then in registration with the locking members 42, which members extend up- -wardly through the-opening 65 when the plate 60 is resting on the top walls. The tongues 64 cooperate with the edges of the openings 31 to tie the rear ends of the cases together and the locking members 42- cooperate with the edges of the openings 65 to tie the forward ends of the cases together. Thus the locking members 42 and the edges of the openings 65 and the tongues 64 and openings 31 form shoulders that cooperate to prevent sliding of the plate relative to the cases. The plate 60 is locked in position by a key 41, the parts of which key cooperate with the locking member 42 and plate 60 in a manner similar to that described above with reference to the locking of adjacent walls of cases. Where three or more stacks form a cabinet a plate 60 connects each top case with an adjoining top case and a top case flanked by two other cases will have one of its locking members 42 locked in one opening 65 of one plate 60 and the other locking member in one opening 65 of another plate 60. Likewise one of the openings 31 in the top wall of the flanked case will have a tongue 64 of one plate 66 extending therein and the other opening 31'will have the tongue 64 of another plate 60 extending therein. It is apparent that the plates 60 will not only tie the top cases together, but also will cover the crevice between the cases of adjacent stacks.

The bottom cases are tied together by plate 6|, which plate is pierced adjacent one end to form two slots 66 that are similar in size to the openings 31 in the top walls of the cases. Two locking members 61 are formed adjacent the front of the plate, which members 61 are similar to the locking members 42 formed on the top walls of the cases. The plate 6| is placed on the support for the cabinet 20, for example a floor, and the bottom cases of the two stacks forming the cabinet are placed on the plate with the adjoining edges of the bottom walls thereof disposed along the center of the plate. The openings 66 are spaced so that a tongue 31, of each case, adjacent the adjoining edges of the two cases, may be inserted therein and the locking members 61 are spaced to be inserted in an opening 4| of each of the adjoining cases. The tongues 31 may be inserted in the openings 66 by sliding the cases rearwardly. When the cases are set onthe support the ends of the tongues 31 will bend upwardly against the under side of the plate BI, and the locking .members 61 will protrude into the interior of the cases through the openings 4|. The tongues 31 cooperate with the edges of the openings 66 to tie the rear end of the cases together and the locking members 61 cooperate with the edges of the openings 4| to tie the forward ends of the cases together. The tongues 31 and the edges of theopenings 66 and the members 61 and openings 4| form shoulders that cooperate to prevent sliding of the plate relative to the cases. The plates are locked in place by keys similar to the key 41, the parts oi which keys cooperate with the locking members 61 in a manner similar to the cooperation of the key 41 with the locking members 42 when two stacked cases are locked together. Where three or more stacks of cases form a cabinet, a plate 6| connects eaeh'adjoining bottom case and a case flanked on either side by other cases will have a plate connected with each of its tongues 39 andopenings 4|. In that instance a key 41 will lock each of the two plates to the case. The plate 6| is relatively thin and the bottom walls are suillciently resilient that the case walls extendingbeyond the edges of the 4 plate will rest on the floor, or other support, and

the cabinet will not tilt by reason of the presence of the plate.

A plate 10 is provided for tying the cases of adjoining stacks together intermediate the top and bottom of the stacks to prevent buckling or bulging of the stacks.- The plate 10 has two spaced openings 1| formed therein adjacent one end thereof which openings are similar in shape to the openings 4| in the cases and are spaced apart the same, distance as the openings 4|. A

pair of openings 12 are formed in the plate 10 at the opposite end thereof which openings are similar in shape to the' openings 66 in the'plate 6| and are spaced apart the same distance as the openings 66. Referring to Fig. 11, a partially formed cabinet is shown having the stacks only partially built. The cabinet is being formed of stacks placed side by side and also back to back. The plates 10 are positioned to'overlap the adjacent edges of two cases of adjacent stacks and having one of the locking members 42 of one of the cases extending through one of the openings 1| and the locking member 42 of the other case extending through the other of the openings 1|. The openings 12 are in registration with one of the openings 31 01 the two cases respectively.

Other cases are then stacked on the partiallyare used to lock the locking members 42 in place in the same manner as explained above. Thus the plates 10 are secured to each of the cases by the. locking members 42 and the tongues 39 of each casing extend through the openings in the plate. The plates 10 are relatively thin so as not to prevent the locking members 42 orthe tongues 39 from extending into the lower cases when the cases are stacked.

When two rows of cases are stacked back to back, as illustrated in Fig. 11, it is desirable to attach cases of one row to cases of the other row to prevent tilting of the cases. An interlock plate 15 is provided, which plate is turned at either end to form shoulders 16. The shoulders 16 are spaced apart the distance between two openings 31 of two cases disposed back to back so that the plates 15 may interconnect the top walls of the two cases with the shoulders 16 inserted in the openings 31. referably the width of the plate 15 is the same as the width of the'openings thereof in which the plates II may lie. The plates 15 are of thin material so that the shoulders 16 do not interfere with the insertion of the tongues 39 into the openings 31.

It is to be noted that the openings 31, tongues 39, openings 4| and locking members 42 are spaced apart from one another on their respective walls so that when two cases are disposed side by side the distance between like adjacent openings, tongues, and locking members of adjacent cases will be the same as the distance between like openings,.tongues or locking members of the same case. Thus the same key 41 may be used to lock two stackedcases together as well as for tying together cases in adjacent stacks.

Preferably the locking mechanism at the front end of the cases is interposed between the paths of the gliders 35 and therefore such mechanism does not obstruct or hinder the gliding movement of the drawer, the gliders being of sufiicient height to raise the bottom wall 34 above the interlocking mechanism.

Preferably the sheet'metal walls of the cases including the drawers, the key 41, the plates 60, GI, and it are formed of cold rolled steel. Cold rolled steel of twenty-four, twenty-six or twentyeight gauge is satisfactory. The thicknesses of the materials herein shown including the reenforcing ring 30 have been exaggerated for the purpose of clearly showing all of the elements of the invention but it is apparent from the disclosure that when these materials are of proper thickness, I have provided an interlocking mechanism which requires only the minimum amount of space, the interlocking mechanism being substantially of the same thickness or slightly less than the thickness of the reenforcing ring 30. Therefore'no space whatever is lost in including this interlocking mechanism in the type of case employing a thin reenforcing ring.

While the form of embodiment of the present invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

I claim:

1. A filing cabinet comprising in combination, two file cases, one of said cases having a plurality of openings in a wall thereof next adjacent a parallel wall of the other case, said other case having a plurality of spaced locking members, one of said members extending through one of said openings and another of the members extending through another of said openings and each of said members having an opening in the part thereof projecting into the first mentioned case; and a furcated locking key including legs extending through the openings in said projecting parts and engaging the inside surfaces of the walls of the locking members, said key including another leg extending alongside one of the locking members and engaging the inside surface oi said wall of the first mentioned case.

2. A filing cabinet comprising in combination, two file cases, one of said cases having a plurality of openings in a wall thereof next adjacent a parallel wall of the other case, said other case having a plurality of spaced locking members, one of said members extending through one of said openings and another of the members extending through another of said openings and each of said members having an opening in the A part thereof projecting into the first mentioned case; and a furcated locking key including legs extending through the openings in said projectcluding anintermediate leg' extending alongside one of thelocking members and engaging the inside surface of said wall of the first mentioned case.

3. A filing cabinet comprising in combination, two filecases, one of said cases havinga plurality of openings in a wall thereof next adjacent a parallel wall of the other case, said other case having a plurality of spaced locking members, one of said members extending through one of said openings and another of the members ex-' tending through another of said openings and each of said members having an opening in and a shoulder on the part thereof projecting into the fi st mentioned case, said last openings each being disposed at one side of a member and the shoulder on the opposite side; and a furcated locking key including legs extending through the openings in said projecting parts and engaging the inside surfaces of the walls of the locking members, said key including portions extending alongside the locking members and engaging the.

inside surface of said wall 01' the first mentioned case and having shoulders abutting shoulders on the locking members. i

4. A filing cabinet comprising-in combination, two file cases, one of said cases having a plurality of openings in a wall thereof next adjacent a parallel wall of the other case, said other case having a plurality of spaced locking members, one of said members extending through one of said openings and another of the members extending through another of said openings and each of said members having an opening in and a shoulder on the part thereof projecting into the first mentioned case, said last openings each being disposed at one side of a member and the shoulder on the opposite side; and a furcated locking key including legs extending through the openings -in said projecting parts andengaging the inside surfaces of the walls of the locking members, said key including portions extending alongside the locking members and engaging the inside surface of said wall of the first mentioned case and having shoulders abutting the shoulders on the locking members, said portions being flexible and resilient with respect to the first mentioned legs so that said shoulders of said portions can be flexed over the locking members when the first mentioned legs are inserted into or removed from the openings in the locking members.

5. A filing cabinet comprising in combination, two file cases disposed adjacent one another and each having a wall disposed in substantially aabutting the shoulders of the locking members.

6. A filing cabinet comprising in combination, two filecases disposed adjacent one another and each having a wall disposed in substantially a common plane, each of said walls having a locking member extending therefrom, members each having an opening therein and having a shoulder; and a key including two legs and a yoke connecting the legs, said legs extend- -ing into the openings in the locking members said locking two file cases disposed side by'side, the top-wall of each of said cases having alocking memberextending therefrom, said locking members each having an opening therein and a shoulder; and a key including two legs and a. yoke connecting the legs, said legs extending into. the openings in the locking members and engaging the inside walls of the locking members, said key also ineluding portions extending alongside the locking members and having shoulders abutting the shoulders of the locking members.

8. A filing cabinet comprising in combination, two file casings, said casings being disposed adjacent one another and each having a wall disposed substantially in a common plane; a plate connecting said walls; means forming a shoulder on each of the two walls and two shoulders on the plate, the shoulders on the plate cooperating with the shoulders on the walls for preventing sliding movement of the walls with respect to the plate, two of said shoulders being formed by protruding members having openings formed therein; and a key including two legs connected. by a yoke, said legs extending into the openings in the protruding members and engaging inside walls of the members, said key also including portions extending alongside theprotruding members, said portions having shoulders engaging said members.

9. A filing cabinet comprising in combination, two file casings, said casings being disposed ad'- jacent one another and each having a wall disposed substantially in a common plane; a plate connecting said walls; means forming a shoulder on each of the two walls and two shoulders on the plate, the shoulders on the plate cooperating with the shoulders on the walls for preventing sliding movement of the walls with respect to the plate, two of said shoulders being formed by protruding members having openings formed therein; and key means including legs extending into the openings in the members and engag-' ing inside walls of the members, said key means also including portions extending alongside. the

protruding members and having shoulders for engaging the members.

10. A filing cabinet comprising in combination, two file casings, said casingsbeing disposed adjacent one another and each having a wall disposed substantially'in a common plane; a plate connecting said walls; means forming a'shoulder on each of the two walls and twoshoulders on the plate, the shoulders on the plate cooperating with the shoulders on the walls for preventing sliding movement of the walls with respect to the plate, two of said shoulders beingformed by protruding members having openings formed therein; and key means including legs extending in the openings in the'members and engaging inside walls of the members, said key means also including portions extending alongside the protruding members and having shoulders for engaging the members, said portions being flexible and resilient with respect to the legs so that the shoulders thereof can be flexed over the protruding members when the first mentioned legs are inserted into or removedirom the openings in the said members.

' 11. A filing cabinet comprising in combination, two file casings, said casingsbeing disposed adjacent one another and each having a wall disposed substantially in a common plane, a plate connecting said walls; means for slidably attaching a portion of the plate to the walls; means forming a shoulder on each or the two walls and two shoulders .on the plate, the shoulders on the plate cooperating with the shoulders on the walls forpreventing sliding movement of the walls with respect-to the plate, two of said shoulders n being formed by protruding-members having openings formed therein; and a key including two legs connected by a yoke, said legs extending into the openings in the members and en-' gaging inside Walls of the members, said key also including portions extending alongside the protruding members and having shoulders .for engaging said members.

12. A filingcabinet comprising in combination, two file casings, said casings being disposed ading therein and each'having a shoulder; and

key means including legs adapted to extend into the openings in the protruding parts and engage an insidewall of the parts, said key means also including portions adapted to extend alongside 13. A filing cabinet comprising in combination,

two file casings, said casings being disposed adjacent one another and each having a wall disposed substantially in a. common plane; a plate.

connecting said walls, said plate having openings therein; locking members formed on the walls,v

said locking members having protruding parts extending'thr'ough the openings in the plate; and p a key including two legs and a yoke connecting the legs, said legs extending into the openings in the locking members and engaging the inside walls of the locking members, said key also ineluding portions extending alongside the locking members and having shoulders. abutting the shoulders on the locking members..

1% A filing cabinet comprisingin combination,

two file casings, said casings being disposed adjacent one another and each having a wall disposed substantially in a common plane; a plate ders being .formed by protruding members havingopenings formed therein; and a key including two legs connected by a yoke, said legs extending into the openings in the members and engaging inside walls of the members, said key also' including-portions extending alongside the protruding members and having shoulders for engaging said members.

15. A filing cabinet comprising in combination, two stacks of file cases disposed side by side, each of said stacks comprising at least two file cases disposed one 'on another, one case of each stack having an opening in a wall thereof next adjacent a wall of the other case; a member on said other case extending into the: opening for attaching the two cases together, said stacks being disposed adjacent one another for forming two tiers of file cases; a plate interconnecting said stacks, said plate having a portion thereof interposed between the adjacent walls of the cases forming one stack and a portion thereof inter posed between the'adJacent. walls of the cases forming the other stack, said; portions each having an opening in registration with the members of said cases, the edges of said openings being adapted to engage the members for preventing separation of the adjacent cases of the adjacent stacks.

16. A filing cabinet comprising in combination, two file casings disposed adjacent one another and each havinga wall disposed in substantially a common plane, each of said walls having an opening therein; and a flat locking key for locking the casings together, said key including a fiat yoke and a plurality of legs extending from one edge of the yoke,'one of said legs extending into one of said openings and alongside the inner surface of one of the casings and another of said legs extending into the other of said openings and alongside the inner surface of the other of the casings and a third leg of said key extending parallel with the said walls of the casings and on the outside of the casings.

17. A filing cabinet comprising in combination, tion, two file casings, said casings being disposed adjacent one another and each having a wall disposed substantially in a common plane; a plate connecting said walls, each of said walls having an opening and said plate having openings registering with said openings in the walls to form passages from the exterior of the casings to the interiors thereof; and a key including twolegs connected by a yoke, said legs extending into said passages and alongside the interior of said can ings, respectively, said key also including a leg extending alongside the plate on the exterior-of the casings.

18. A filing cabinet comprising in combination, two file casings, said casings being disposed ad- Jacent one another and each having a wall disposed substantially in' a common plane; a plate connecting said walls, each of said walls having an opening and said plate having openings registering with said openings in the walls to form passages from the exterior of the casings to the interiorsthereof; and keys for interlocking the plate and casings, each of said keys including a yoke and two legs extending from the yoke, the yoke and one of said legs extending alongside the interior of a casing and the other of said legs extending through one of the passages and alongside the exterior of the plate.

19. A filing cabinet comprising in combination, two file cases, 'said cases having walls arranged in side to side relation, one of said walls having a plurality of openings; means on one of said.

walls forming a shoulder adjacent each of said openings, said shoulders extending inwardly with respect to said one wall, and bulged portions extending through said openings and inwardly with respect to said one wall, said bulged portions being connected with the other of said walls and having mouths cooperating with edges of said openings for forming a plurality of spaced key passages; and a furcated locking key including legs extending into said passages, said key including a portion extending alongside at least one of said openings and having a shoulder abutting one of the first mentioned shoulders adlacent said one opening. 

